if I want to become a doctor which program for high school is best, Advanced placement (ap) or International Baccalaureate (ib)? and what's the difference between ib and ap?

Without stratospheric ozone, which of the following would most likely occur? i. smog over major cities would be greatly reduced. ii. farms would produce surplus crops because of increased photosynthesis. iii. uv radiation would damage phytoplankton and reduce populations of aquatic consumers. i only ii only iii only i and ii i and iii